arcasii, Leucos Steindachner [F.] 1866:14 [Anzeiger der Kaiserlichen Akademie der Wissenschaften, Mathematisch-Naturwissenschaftlichen Classe v. 3; ref. 21709] Ebro River at Logroño, La Rioja, and Cailes [Queiles] River at Tudela, Navarra, Spain. Syntypes: (many) NMW 50639-49 (3, 2, 3, 4, 3, 30, 2, 5, 6, 20, 9), 50650-51 (3, 27), 49760 (4), 49752-777 (75 spec., 26 lots), 60743 (1), 60485 (1). Species first described in the abstract above, later described in more detail in Steindachner 1866 [ref. 14058], p. 199 [p. 2 of separate]; also appeared in Steindachner 1866:14 [p. 9 of separate] [ref. 18776] as Leuciscus (Leucos) arcasii and in Steindachner 1866:311 [ref. 21711] and Steindachner 1866:5 [ref. 18757] as Leuciscus arcasii. Misspelled arca by Seeley 1886:179 [ref. 30373] in genus Leuciscus. •Valid as Rutilus arcasii (Steindachner 1866) -- (Kottelat 1997:76 [ref. 22952]). •See Ketmaier et al. 1998:47 [ref. 23809]. •Valid as Chondrostoma arcasii (Steindachner 1866) -- (Doadrio & Carmona 2003:30 [ref. 28132], Coelho et al. 2005:202 [ref. 28430], Robalo et al. 2005:24 [ref. 28431], Gante et al. 2007:26 [ref. 29300], Gante et al. 2010:968 [ref. 35176]). •Valid as Achondrostoma arcasii (Steindachner 1866) -- (Robalo et al. 2007:370 [ref. 28878], Doadrio & Elvira 2007:296 [ref. 29510], Kottelat & Freyhof 2007:156 [ref. 29996], Perea et al. 2010:14 [ref. 31802], Doadrio et al. 2023:7 [ref. 40184]). Current status: Valid as Achondrostoma arcasii (Steindachner 1866). Leuciscidae: Leuciscinae. Distribution: Southwest Europe: Ebro and Levantine (Mijares, Turia and Palancia) drainages, Spain. Habitat: freshwater.